1. Field of the Invention
The present invention relates to a continuously variable transmission of a straddle-type vehicle, and in particular, to a technology for adjusting the position of the center of gravity of a clutch.
2. Description of Related Art
Some straddle-type vehicles such as motorcycles have a clutch for transmitting or interrupting torque to a rear wheel and a continuously variable transmission for continuously varying a speed change ratio. When a belt-type continuously variable transmission is operated, a pulley around which a belt is wound is rotated around a shaft by the torque of an engine. Some clutches include a clutch inner and a clutch outer for housing the clutch inner and transmit or interrupt torque between the clutch inner and outer.
A member rotating around a shaft such as a clutch and a pulley may have a center of gravity shifted from the center of rotation by a manufacture error, which causes vibration and degrades the ride comfort of the vehicle. To bring the position of the center of gravity of the member close to the center of rotation, a technology for manufacturing a portion of the member is proposed in the related art. See, for example, Japanese Examined Utility Model Publication No. 63-7725.
However, in the related art, the manufacturing work for bringing the position of the center of gravity close to the center of rotation decreases manufacturing efficiency. For example, in a case where a member is small in size, such as in a clutch or continuously variable transmission for a small motorcycle, the manufacturing range in a clutch or a pulley also becomes small. Hence, when the position of the center of gravity is greatly shifted from the center of rotation by a manufacture error, the member itself needs to be replaced. Moreover, when the work of adjusting the position of the center of gravity is performed in the state that the pulley of the continuously variable transmission is mounted in an engine unit, it is difficult to perform manufacturing work because the pulley is positioned inside in a vehicle width direction (near the center of a shaft).